Archived posting to the Leica Users Group, 1999/03/25
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]To: John Gong <jgong@cisco.com> No, Terry IS referring to an extension tube. You are correct in stating that an extension tube generally is used for macro photography. What Moose Peterson has done, as well as many wildlife photographers, is to use an extension tube on a long telephoto to decrease the minimum focus range of the long telephoto. This does allow you to come in closer to the subject in the field and essentially "magnify" the image on the film. Just as in macro photography, as you state. But what this also does is to separate the subject from the background as well. You maintain that same narrow depth of field demonstrated by a 400 @ f2.8 or 500mm @ f4.0, etc, but since the subject is so much closer, the background is even further away. The result is a wonderfully "blown away" background. <snip> I really don't understand this proposal. An extension tube physically moves the lens outboard from the body. The intent is for macrophotography, as the focus point moves such that close focus is possible, but at the disadvantage of losing distant focus. If your intent is to photograph wildlife other than insects at close range, I'm afraid an extension tube is not what you need. Your extenders are intended to permit an increase in effective focal length and preserving your focus range on a lens. Are you sure this isn't what Moose used instead? With the increase of focal length, shortened depth of field results in nice blurred backgrounds. <snip>